Killer Infinite: a killer sudoku that never ends

I love Killer Sudoku. I also have a complaint about it, and it took me a while to admit what it was. A single Killer puzzle has a shape. The opening is hard, sometimes hard enough to stall you before you have placed a single digit. The middle is the good part, where the cages start talking to each other and numbers fall into place. The end is cleanup. By then the puzzle is basically solved and you are just writing it down.

The opening is the bit that loses people. No given digits, just cages and sums. You stare at an empty grid and wait for a foothold, and if you do not know the cage tricks yet, that wait can be the whole game. (If that is you, the killer cages guide walks through the forced ones.)

The ending is a quieter kind of letdown. The hard thinking is done, the tension is gone, and the last handful of cells are a formality. So the part I actually play for, the middle, sits between a wall at the front and a shrug at the back.

So I built Killer Infinite. It does not end. When you finish a board, the next one slides in on a diagonal, and the two grids share a seam. The cells you just solved carry over into the corner of the new board. You are never handed a blank grid.

That shared seam is the whole idea. It is a foothold you did not have to dig for. No cold open, no staring, no wall. You step off one board straight into the middle of the next, which is exactly where Killer is most fun.

It runs in days and levels, so there is always a next one waiting. Play for five minutes or an hour, the board just keeps flowing. All the parts I like, none of the parts I don't.

You can play it in Coffee Sudoku on iPhone and Android, or in your browser at coffeesudoku.com. No login, no ads. Bring your coffee and see how far you get.